Update Dockerfile

Dockerfile

@@ -4,13 +4,10 @@ FROM python:3.9-slim
 # Set the working directory inside the container
 WORKDIR /app
 
-# --- THE CORRECT FIX ---
-# 1. The Debian 10 "Buster" repository is now on the archive server. We must point to the correct URL.
-# 2. We add "[trusted=yes]" because archived repositories may have expired GPG keys.
+# Add the archived Debian repository to find old libraries
 RUN echo "deb [trusted=yes] http://archive.debian.org/debian buster main" > /etc/apt/sources.list.d/buster.list
 
-# Now, update the package lists. This will successfully find the old packages on the archive server.
-# Then, install all the necessary system libraries, which will now be found.
+# Update package lists and install all system dependencies
 RUN apt-get update && apt-get install -y --no-install-recommends \
     wget \
     fontconfig \
@@ -23,7 +20,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/*
 
-# With all dependencies correctly installed, download and install the wkhtmltox package.
+# Download and install the wkhtmltox package
 RUN wget https://github.com/wkhtmltopdf/packaging/releases/download/0.12.6-1/wkhtmltox_0.12.6-1.buster_amd64.deb && \
     dpkg -i wkhtmltox_0.12.6-1.buster_amd64.deb && \
     rm wkhtmltox_0.12.6-1.buster_amd64.deb
@@ -32,11 +29,13 @@ RUN wget https://github.com/wkhtmltopdf/packaging/releases/download/0.12.6-1/wkh
 COPY requirements.txt .
 COPY app.py .
 
-# Install the Python dependencies
+# Install the Python dependencies (including gunicorn)
 RUN pip install --no-cache-dir -r requirements.txt
 
 # Expose the port that Flask will run on
 EXPOSE 7860
 
-# The command to start your Flask application when the container launches
-CMD ["python", "app.py"]
+# --- THE CORRECTED FINAL LINE ---
+# Use gunicorn to run the app. It's a production server that integrates properly with the platform.
+# It looks for the 'app.py' file (module) and the 'app = Flask(...)' object (instance).
+CMD ["gunicorn", "--bind", "0.0.0.0:7860", "app:app"]